Two cases of cystic pulmonary hamartoma are reported with the clinical, roentgenographic and histopathologic findings. Both patients were asymptomatic, and the lesions were discovered on routine chest roentgenography. Physical examination and laboratory data revealed no significant abnormal findings, but CT scans of the chest showed cystic change in both lesions. The histopathologic pictures of the lesions were characterized by a composition of glandular bronchiolar structures lined with ciliated cuboid epithelium and fibrous connective tissue. One case demonstrated interlacing, communicating bands and whorls of smooth spindle muscle cells with elongated nuclei and rounded blunt ends. Neither the epithelial, nor muscular fibrous tissue elements exhibited any degree of anaplasia. The two patients were followed up for 10 months and 3 years, respectively. They both showed no signs of recurrence or distant metastasis.